A technique for delivering harmful biological agents to enemy battlefield combatants is in an aerosol. The microscopic agent particles are usually dry, but could be carried in a compatible liquid. That material is sprayed or otherwise released into the atmosphere as an aerosol by an exploding shell, a missile or an aircraft in the general vicinity of the targeted combatants. Depending on the prevailing winds, the aerosol or cloud, as variously termed, may be released some distance from the target combatants and the prevailing wind is allowed to carry the cloud to the location where the combatants may be exposed.
In one dictionary definition, the term cloud is defined as a visible mass of minute particles suspended in the air or in a gas. The term aerosol is defined as a suspension of fine solid or liquid particles in gas. Smoke, fog, and mist are given examples of an aerosol. Significant overlap is apparent. Aerosol also refers to the manner in which the particles were dispensed into the air, i.e. a substance dispensed from a pressurized container as an aerosol.
As becomes clear from study, agent particles may be so small and the density very light so that the mass of those suspended particles need not be visible to the naked eye. As one also understands, the particles may be small and heavier than air, and yet may be suspended in the air, even though individually the particles are heavier-than-air. Even though suspended in air, if the ambient air remains still, the particles may settle out of suspension and deposit on surfaces, remaining just as deadly. The toxin Anthrax is an example of the latter. It should thus be understood, that all those possibilities are encompassed within either of the terms aerosol or cloud as used in this application, whether the particles are visible to the eye or not, and the terms subsume such extensions of the dictionary definitions.
Currently, there is no good method known for remotely and directly detecting the presence of aerosolized biological agents. Toxins are particularly troublesome because they are fast-acting and disabling. Some of the more notorious toxins include botulism toxin, staphylococcal enterotoxin B, and ricin. By the time sensors of existing design are able to produce an alarm, personnel are already sick, in the throes of dying or already dead. The picture is not pretty.
Some might urge that detection of agent aerosols lacks utility, since that form of warfare has been outlawed by treaty and all world organizations. Notwithstanding, not all nations subscribe to those treaties and, of course, treaties have at times been broken or rationalized by renegade nations. The problem remains. Hence, there remains utility in detecting airborne agents. The result is that the prudent nation should develop defensive measures. Detection techniques are an appropriate part of those measures. And that's only the military picture, where one nation wishes to destroy clusters of troops of another nation on the battlefield.
A mentally deranged person who possesses a can of aerosol filled with a biotoxin may be able to rent and pilot a small plane to spray the aerosol over New York City, as example, a favorite symbolic spot. It's easy to obtain the small plane, and even to rent a pilot. Obtaining the biotoxin is not so simple, yet not impossible. And the targeted victims or their protectors the police and the military cannot detect the oncoming cloud of antigens in a timely manner. At best, they might rely on the Biowatch system, which currently provides warning in days, not minutes or hours.
Accordingly, an object of the invention is to provide warning of a toxin laden cloud.
A further object of the invention is to detect toxin laden clouds in sufficient time to allow targeted persons to take protective measures to avoid or defeat the toxicity.